Carbon Dioxide Tolerance and Toxicity

Rubicon Research Repository/Manakin Repository

Carbon Dioxide Tolerance and Toxicity

Show full item record


Title: Carbon Dioxide Tolerance and Toxicity
Author: Lambertsen, CJ
Abstract: Carbon Dioxide is a normal body constituent, continually produced by oxidative metabolism. Its hydration leads to formation of hydrogen ions and the establishment of a bicarbonate buffer system in blood and other vital body fluuids. In its numerous normal roles in body function carbon dioxide is a key chemical messenger substance in the linking of respiration, general circulation and local vascular responce to the demands of metabolism both at rest and exercise. In its normal, active role as an agent in the respiratory, circulatory and renal control systems, intrinsically produced carbon dioxide is not a toxin. It is an essential factor in the determination of the normal acid-base balance required for enzymatic reactions. Inhaled carbon dioxide produces the same physiological effects as does carbon dioxide produced metabolically. These effects appear to result from the acidosis induced by carbon dioxide reaction with water, rather than by the CO2 molecule itself. Toxic effects of CO2 do occur when such high concentrations of CO2 are inhaled that severe and disruptive cellular acidosis occurs. This acidosis and its effects are alleviated by lowering the inhaled concentration of CO2. Adaptation to moderate inspired concentrations of carbon dioxide (to three and four percent) occurs in normal men who can tolerate continuous inhalation of three percent inspired CO2 for at least one month and four percent inspired CO2 for over a week. Because the effects produced by low and moderate concentrations of carbon dioxide are physiological and reversible, rather than toxic and damaging, it is recommended that the allowable inspired levels of carbon dioxide be increased from 0.5 to 2.0 percent in inspired air. This level has not been shown too induce decrement in performance or in normal physical activity.
Description: The items forming the Rubicon Research Repository Christian J. Lambertsen collection are generously donated by the Lambertsen Family. All items in this collection are released through Creative Commons Attribution + Noncommercial + ShareAlike (BY-NC-SA) licenses in an attempt to encourage the use of these works to further scientific understanding of physiology.
URI: http://archive.rubicon-foundation.org/10771
Date: 1971

Files in this item

Files Size Format View
Carbon_Dioxide_Tolerance_and_Toxicity_1971.pdf 8.772Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record

Browse

My Account